2001ApJ...558L..83O

We study the clustering properties of about 1200 z∼4 Lyman break galaxy (LBG) candidates with i'<26 that are selected by color from deep BRi' imaging data of a 618 arcmin² area in the Subaru/XMM-Newton Deep Field taken with Subaru Prime Focus Camera. The contamination and completeness of our LBG sample are evaluated, on the basis of the Hubble Deep Field-North (HDF-N) objects, to be 17% and 45%, respectively. We derive the angular correlation function over θ=2''-1000'' and find that it is fitted fairly well by a power law, ω(θ)=A_ωθ^–0.8, with A_ω=0.71±0.26. We then calculate the correlation length r₀ (in comoving units) of the two-point spatial correlation function ξ(r)=(r/r₀)^–1.8 from A_ω using the redshift distribution of LBGs derived from the HDF-N and find that r₀=2.7^+0.5_–0.6 h^–1 Mpc in a Λ-dominated universe (Ω_m=0.3 and Ω_Λ=0.7). This is twice as large as the correlation length of the dark matter at z≃4 predicted from an analytic model by Peacock and Dodds but about twice as small as that of bright galaxies predicted from a semianalytic model by Baugh and coworkers. We find an excess of ω(θ) on small scales (θ≲5''), departing from the power-law fit by over 3 σ significance levels. Interpreting this as being due to galaxy mergers, we estimate the fraction of galaxies undergoing mergers in our LBG sample to be 3.0%±0.9%, which is significantly smaller than those of galaxies at intermediate redshifts.